1. Field of the Invention
The present invention relates to printers, and, more particularly, to a print medium exit system for a printer.
2. Description of the Related Art
Most ink jet printers have a star-wheel exit system in which the star-wheels are directly linked to a feed roll shaft. The feed roll shaft simply keeps turning forward to drive print media out of the printer after printing. A problem is that the star wheels touch the printed surface of the paper and sometimes cause the ink to smear or cause small xe2x80x9cstar wheelxe2x80x9d tracks on the printed image.
It is also known to control the exiting media in an exit system by requiring motion of a printhead carrier or some other power source. For instance, in a kicker exit system, the kickers emerge from behind a final nip and push/kick the print media out of the printer. The kicker exit system has the advantage that the printed surface of the paper is never touched, so there is no smearing of the ink. Unlike the star-wheel exit system that runs all the time because it is always linked to the feed roll shaft, the kicker exit system requires activation because it only needs to run after a print job. The printhead can be used to activate the kicker system. However, using the printhead has some disadvantages, such as decreasing throughput. This is especially true if the printhead carrier is away from the kicker mechanism because it takes time to bring the printhead over to a desired location for activation. Also, problems may result if the printhead has to go through a maintenance cycle during an exit operation.
What is needed in the art is a paper exit system that does not touch the printed surface of the paper and that is not activated by a printhead carrier.
The present invention provides a kicker media exit system activated by a mechanical clutch controlled by the presence of media passing through the nip.
The invention comprises, in one form thereof, a print medium exit system in a printer. A kicker device ejects a sheet of print medium out of the printer. A clutch mechanism prevents actuation of the kicker device when the clutch mechanism is engaged by the sheet of print medium.
The invention comprises, in another form thereof, a method of ejecting a sheet of print medium from a printer. It is sensed when the sheet of print medium is at a predetermined location along a paper path in the printer. A print medium exit system is activated dependent upon the sensing step.
An advantage of the present invention is that the exit system does not touch the printed surface of the paper, so no smearing of the ink occurs.
Another advantage is that the kicker exit system is not activated by a printhead carrier, so throughput is increased and positioning issues are eliminated.